For reports created from 22 January 2018, the fields
rowCount and maxRows allow
you to see how close you are to reaching the limit of 100000
rows per report. If the data you are querying for exceeds the
100000 rows limit, your report will be incomplete.

To make sure you get a complete report, you should query for less data. Try
the following tips:

Split reports based on time period. For example, query for each quarter
separately instead of querying for an entire year.

Remove one or more campaigns or goals from your selected filters, or create
a report per campaign.

Narrow down the data by selecting more filters.

Remove one or more of the selected dimensions. If you have selected one or
more dimensions with a high cardinality, query them separately.

For the Time dimension, select a less granular breakdown of data. For
example, select month instead of day.